Typically, a large portion of the time spent by players in a tennis game is expended retrieving tennis balls from various locations, both on and off the tennis court, where such balls roll dead after one of the players either misses striking the ball with his racket, or strikes it and fails to drive it to the proper area on the tennis court. Such necessity for constantly retrieving the tennis ball after it is knocked out-of-play is laborious and objectionable to many tennis players. This problem is exacerbated during and at the end of tennis practice sessions and clinics, where balls may be hit with no intention of having the ball returned by an opposing player.
One excellent and relatively convenient way for a player to get needed practice is to utilize a ball throwing machine. The use of such machines eliminates the need for a second player or even a regulation size tennis court. Ball throwing machines may be installed in special lanes or practice alleys in which a player practices returning balls propelled by the ball machine. Ball throwing machines typically propel balls in rapid succession. Consequently, a large number of balls are needed to feed the machine in order to keep the machine in operation. Even if the ball thrower is constructed with a large capacity ball hopper, a large number of balls is required to avoid frequent interruptions of practice to pick up the spent balls and reload the ball hopper. Typically, many loose balls remain lying on the court, both distracting the player and providing possible sources of injury if the player steps on or trips over a loose ball.
To avoid these disadvantages and meet the ball requirements for these automatic machines, ball retrieval machines have been developed to retrieve balls previously thrown and to transport them to the intake of the ball throwing machine. One such type of machine uses an air pressure source to propel balls through a tube from a collection point, such as at the bottom of a slope or incline constructed in the playing surface, to the intake of the ball throwing machine.
Many solutions to the problem of retrieving scattered tennis balls have been suggested and implemented. One early solution was to hire a “ball boy” to actively retrieve tennis balls during a practice session or game. This solution added another person moving around the court and surrounding areas and proved distracting to many players. In addition, there was the expense of paying the “ball boy”.
Various mechanical devices have been proposed for collecting tennis balls after a game, practice session, or clinic. One such device is the subject of U.S. Pat. No. 3,819,049 for BALL RETRIEVING APPARATUS, issued Jun. 25, 1974 to Francis Koerner et al. Koerner describes a vacuum cleaner-like device for sucking up and storing tennis balls from around the court. This again requires a person to move the device around the area having tennis balls to be retrieved and balls are collected on a one-at-at-time basis.
Yet another method of collecting tennis balls from half of the tennis court consists of two ribs, one rib of which normally is located along each of two opposite edges of the court half. A drive system draws the ribs toward each other while conveying balls on the court surface, thereby to collect the balls from a limited area, and then to return the ribs to their original position. Controls for means are arranged to control the drive means. The controls are preferably actuatable by the player and from a position located within the limited ball-collecting area. Preferably at least one of the ribs is arranged to be angled or curved in the horizontal plane, such that the concave side of the rib faces the other rib. Even with such an apparatus, balls must be manually retrieved and transported.
Yet another ball retrieval system found in the prior art is a system wherein the entire tennis court may be selectively tilted to force tennis balls to roll down the tiled tennis court to a collection area. An added advantage to this system is that the court may be disposed in a tilted position during a rain storm so water does not collect on the surface. Once rain stops, the tennis court is leveled and playing can be started quickly.
Still another retrieval system has a ball retrieval arm mechanism extending from the base line to the tennis net on a tennis court. The arm may be moved along the net. During the retrieving process, the retrieving arm moves only one time during each passage in a transverse direction over one half of the tennis court. The retrieving arm continues its movement until it reaches one side edge of the tennis court. Ball receiving channels are provided along both sides of the tennis court, into one of which the balls are thrust by the retrieving arms and transported by one or more conveyor belts to one top end of the tennis court. The ball receiving channels have connections to a conveyor chute by which the balls are transported from the corners of the tennis court to a ball retriever placed in the middle of the top of the tennis court or to a ball retriever directly.
It would, therefore, be advantageous to provide a system for quickly gathering dead tennis balls from a tennis court with little or no human intervention using air directed along the surface of the tennis court. It would be further advantageous to have features within the ball gathering system to dry the surface of a tennis court after rain or other deposition of moisture on the tennis court surface.